From fbd36b8e0b8a88dbbe4daf8af39e89414a4a91ae Mon Sep 17 00:00:00 2001
From: Joe Savona <joesavona@fb.com>
Date: Mon, 9 Jun 2025 11:11:16 -0700
Subject: [PATCH] Update base for Update on "[compiler] Distinguish
 Alias/Assign effects"
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Alias was akward becuase it had a specific data flow / mutability relationship — direct mutations affect both sides - but also populated the output. We need the ability to express the aliasing dataflwo/mutability relationship w/o expressing actual assignment.

An example of this is that for an unknown method call `const z = x.y()`, we want to express the Alias-style mutability relationship btw z and x (Muate(z) => Mutate(x)), but we want to assume that `z !== x`.

This ends up being really clean, the places that should use Assign are very obvious (LoadLocal, StoreLocal) and most places keep using Alias.

[ghstack-poisoned]